Definitions

1. verb

to become or make something harder or more firm

“The cold winter weather will help the soil harden.”

2. verb

to make someone more determined or less willing to change their opinion

“The news story hardened her stance on the issue.”

3. noun

a covering of ice or frost on a surface

“The harden on the windshield made it difficult to see.”

4. noun

the process of making something harder or more firm

“The hardening of the concrete took several days.”